Novel core-shell type thermo-sensitive nanoparticles composed of poly(gamma-benzyl L-glutamate) as the core and poly(N-isopropylacrylamide) as the shell

AB diblock copolymers consisting of PBLG as the hydrophobic part and PNIPAAm as the hydrophilic one were prepared by polymerization of BLG-NCA with semitelechelic PNIPAAm with amino end group as initiator. The core-shell type nanoparticles of the block copolymers were obtained by the diafiltration method. The sizes of the nanoparticles were from about 73 to 359 nm and the shapes of them were spherical. The release for indomethacin (LN) from the nanoparticles was faster at 28 degrees C than at 34 degrees C due to the conformational change of PNIPAAm by temperature.